1. Field of the Invention
The present invention relates to a medical instrument used together with an endoscope and to an endoscope system which facilitates various operations of the medical equipment or functional operations of the endoscope.
2. Description of the Related Art
In recent years, endoscopes have been widely used in the medical field. The endoscope generally includes an elongated insertion portion, a bendable bending portion which is provided at the distal end portion of the insertion portion, and an operation portion in which knobs, switches, and the like, for performing various operations of endoscopic functions are provided.
The endoscope allows the insertion portion to be inserted into the body cavity of a subject so that an organ in a body cavity can be observed or a treatment instrument inserted into a treatment instrument channel can be used to perform various treatment operations, as required.
When the treatment instrument is inserted into the treatment instrument channel in the conventional endoscope used for medical treatment, a surgeon manually introduces the sheath of the treatment instrument into the treatment instrument channel while holding the sheath. However, the insertion performed in this way is cumbersome, and further, the insertion of the treatment instrument as long as 2 m requires attentiveness besides the cumbersomeness. Thus, the insertion and various operations of the treatment instrument are very laborious.
In order to solve the above described problems, for example, in Japanese Patent Application Laid-Open Publication No. 57-190541, there is disclosed an endoscope which includes a treatment instrument inserting and extracting apparatus for inserting and extracting a treatment instrument into and from a treatment instrument channel of the endoscope, and in which, when the treatment instrument reaches the vicinity of the distal end of the insertion portion of the endoscope, the mechanical insertion can be cancelled and a delicate insertion can be manually performed.
Further, in Japanese Patent Application Laid-Open Publication No. 2000-207, there is disclosed an endoscope treatment instrument inserting and extracting apparatus which, in addition to a function of inserting and extracting a treatment instrument into and from a treatment instrument channel of an endoscope, includes treatment instrument operation means for operating a treatment portion provided at the distal end of the treatment instrument, and in which various operations of the treatment instrument inserting and extracting apparatus are performed by means of a foot switch.
The treatment instrument inserting and extracting apparatus or the endoscope treatment instrument inserting and extracting apparatus as disclosed in Japanese Patent Application Laid-Open Publication No. 57-190541 or Japanese Patent Application Laid-Open Publication No. 2000-207 include a metallic spiral pipe sheath which is formed by spirally winding metallic non-stranded wires into a tube, a tubular flexible sheath formed of a synthetic resin or an elastic member, and the like.
In these treatment instrument inserting and extracting apparatuses, a treatment instrument is moved forward and backward by the friction between respective roller surfaces of a drive roller for transmitting the torque of a motor and a freely rotatable driven roller, and the treatment instrument sheath surface which is brought into press contact with the roller surfaces.